#!/usr/bin/env python3

import sys


def fail(msg):
    print(msg, file=sys.stderr)
    sys.exit(43)


with open(sys.argv[1]) as infile, open(sys.argv[2]) as ansfile:
    team_output = sys.stdin.read()

    is_impossible = ansfile.read().strip() == 'impossible'
    if is_impossible:
        if team_output.strip().lower() != 'impossible':
            sane_team_output = team_output.rstrip().replace('\n', '\\n')
            if len(sane_team_output) > 80:
                sane_team_output = sane_team_output[:80] + '[...]'
            fail(f"Expected 'impossible', got '{sane_team_output}'")
        else:
            sys.exit(42)  # Team correctly outputs 'impossible'
    # After this, the test case must be possible.

    if 'impossible' in team_output.lower():  # super-lenient about case and spam
        fail("Rejects yes-instance")

    n, m, k = map(int, map(int, infile.readline().split()))
    edges = []
    for line in infile:
        edges.append(line.split())

    team_tokens = team_output.split()
    if not team_tokens:
        fail("Team output is empty")

    try:
        r = int(team_tokens[0])
    except ValueError:
        fail(f"Integer expected, got {team_tokens[0]}")

    if len(team_tokens[1:]) != r:
        fail(f"Team promised {r} vertices, but provided {len(team_tokens[1:])}")

    try:
        U = set(map(int, team_tokens[1:]))
    except ValueError:
        fail(f"Integers expected, got {team_tokens[1:]}")

    # TODO more checks

covered = 0
for e in edges:
    u, v = map(int, e)
    if u in U or v in U:
        covered += 1
if covered != k:
    fail(f"Covered {covered} edges, expected {k}")
sys.exit(42)